# Homework Help: Complex Analysis: Properties of Line Integrals

1. Oct 12, 2011

### tarheelborn

1. The problem statement, all variables and given/known data

Demonstrate that $$\int_{-\gamma} f(z)|dz|=\int_{\gamma} f(z)|dz|$$ where $$\gamma$$ is a piecewise smooth path and f is a function that is continuous on $$|\gamma|$$.

2. Relevant equations

3. The attempt at a solution

This proof seems like it should be very simple, but I am not sure it is really saying that it's just turning a path around to go in the opposite direction. Could someone please help me out? Thanks.

2. Oct 13, 2011

### HallsofIvy

Consider the substitution u= -z.